Flowable materials, in particular, the dry particulate materials, present unique problems in their storage, transportation, dispensing and handling. These materials, for example, include chemicals, fertilizers, minerals, food stuffs, agricultural products and the like.
The bags or containers for these materials are usually flexible so that they can be easily handled, have large capacities and provide top filling and bottom discharge. The bags may be made in several layers to provide the strength that is needed to handle large quantities of product. The bags may be such as those disclosed in U.S. Patent Nos. 3,962,959 and 4,113,146. Of course, smaller sizes of such bags could also be used.
During the filling of such bags with product, because the product is flowable, a great deal of dust is generated which settles on the outside of the bag. Further, during the handling and storage of the bags, they often come in contact with contaminants such as dirt, grease, oil and other substances which when contacted, are deposited on the bag. Such contaminants are not only unsightly, thus rendering the bag unacceptable for a marketing display, but also, in many cases, the product within the bag is a food product which must be protected from contaminants.
The present invention overcomes these disadvantages by providing a protective cover for a flexible semi-bulk bag or container which protects the container from being contaminated with extraneous material during filling, handling and storing.
In the present invention, the protective covering forms no permanent bond with the container which it covers and may be stripped from the outside of the container when the container is ready for marketing and display, thus, presenting a clean container free from contaminants and acceptable to be displayed.
In one embodiment of the invention, the container is coated with a material such as polyethylene which forms no permanent bond to the container and which can be easily stripped from the outside of the container when it is ready for marketing and display.
In still another embodiment of the invention, removable skirts of plastic film or paper or sewn into the top seam of the sack to hang down and cover the sides.
In yet another embodiment of the invention, the protective cover is formed of either plastic film or paper with an opening in the top for alignment with the filler opening of the container and with an opening at each top corner for the lifting straps of the container so that the container, when full, can be lifted by the straps extending through the openings in each corner.
Still another embodiment of the protective cover is in the form of a shaped liner larger than the container and which receives the empty container. Lift straps of the container are inserted through corner slots which have extensions or ears formed therefrom so that once the lift straps are inserted through the extensions, they can be tied off to make a dust-free or tight corner. In addition, the shaped liner has a cover spout through which the fill spout of the container can be accessed so that the container can be filled. The fill sack spout can be closed first and then the cover spout can be tied off to protect contaminants from entering the top of the covering to reach the container. Further, the shaped liner can be made long enough to close or tie off the bottom after the container is filled.